I've had my D300 since Nov 2007 (release month) and have formatted and re-formatted hundreds of times with several different SanDisk Extreme 4GB CF cards with nary a problem - until today - and I leave for a trip to Paris in 3 days!
I routinely delete all images after securely uploading files to my computer by simultaneously pressing the mode + delete buttons twice until the full complement of images on the card appears in the LCD (369 for a 4GB card). That works OK. But for the first time , my attempt to re-format in the tools area in the menu does not work. I move the cursor to 'YES' (since the screen by default opens with 'NO' selected) and when I select yes as I always have, there is no response on-screen and the images are not deleted. As far as I can see, other functions in the menu bank are unaffected, though I haven't tried them all yet.
For my trip, I just received 2 SanDisk Extreme 8GB cards from B&H to accompany a few 4GB ones which I have used many times each. I noticed the problem in the menu tools when I tried to Format the new cards since my understanding is that new cards should be formatted before first use.
I am very concerned that there may be an electrical problem lurking within my D300 which would ruin my vacation entirely.
Does pressing the Delete + Mode buttons twice each for a few seconds actually re-format exactly the same as doing so in the Menu? Or is the 2 button process simply deleting the files but not fully re-formatting the card? I always do it both ways when I want to empty and freshen a card just to be sure. I am concerned about the unused 8GB cards.